Here's a pic. However "safe" this stunt was in terms of risk management, I don't think we should be encouraging people to use their infants as publicity props.
I don't either, but I think the differnce here is that at the zoo, feeding the animals is part of the children's daily experience. If they only participated for the cameras I might be inclined to agree. According to the bio on the Crocodile Hunter website, his daughter was a part of that life from day 1.